Carburetor having a protective cover



1966 N. G. RAMUS 3,269,710

GARBURETOR HAVING A PROTECTIVE COVER Filed Jan. 20, 1964 FIG. .1.

INVENTOR. NICKOLAS G. RAMUS ATTORNEYS United States Patent 3,269,710CARBURETOR HAVING A PROTECTIVE COVER Nickolas G. Ramus, 261 FairmontAve., Apt. 21, Oakland, Calif. Filed Jan. 20, 1964, Ser. No. 338,718 8Claims. (Cl. 261-1) This invention relates to a protective cover for acarburetor and, more particularly, to a protective cover adapted for usein a motorcycle carburetor to prevent entry of dust, moisture and otherforeign matter.

In common use in motorcycles is a small carburetor having an upstandingcylindrical main body portion with an open upper end which is covered bya cap member attached thereon by a threaded connection, either directlyor by means of a threaded coupling. Such carburetors give extremelysatisfactory performance in normal use, but under severe use as inracing, and particularly racing over turf, considerable difficulty iswidely experienced by reason of dirt particles, moisture and the likebeing drawn into the carburetor body through the threaded connection.Such dirt particles or moisture may impede the proper operation ofcarburetor components. For example, they may cause .the throttle valveto stick and, if it sticks in open position, the result may be a runawayengine. Others have attempted to solve this problem by wrappingelectricians tape or the like, around the body and cap to cover thethreaded connection. However, this practice causes considerable expenseand inconvenience in removing and replacing the tape in order to serviceor repair the carburetor.

It is therefore, an object of this invention to provide a protectivecover for a carburetor that may be used repeatedly for an extensiveperiod of time.

It is a further object of this invention to provide a protective coverfor a carburetor that may be applied and removed easily but which willprotect the carburetor against entry of foreign matter.

It is a further object object of this invention to provide a protectivecover for a carburetor that is simple to manufacture and convenient toapply.

In carrying out this invention, I provide an inverted, cup-likecylindrical member of rubber, plastic or similar resilient material thatis normally of a diameter at the bottom open end which is slightlysmaller than the diameter of the carburetor body so that it may bestretched over the body to embrace it snugly. The protective cover is ofsuflicient length to extend from the top of the carburetor down belowthe threaded connection of the carburetor cap, and .the top of the coverhas molded therein one or more tubular protrusions which are adaptedsnugly to embrace conduits leading into the top of the carburetor capsuch as for the throttle adjustment cable. Since certain carburetors inwide use include a spring clip which extends laterally from the cap anddown to engage the threaded coupling frictionally, the protective coveralso has molded integral therewith a lateral extension to accommodatethe spring clip. Thus, the cap may be placed over the top of thecarburetor with the cable a-djuster connection extending through thetubular extension of the protective cover, and the cover then pulledsnugly over the body until the bottom band portion snugly embraces thecylindrical body.

Other objects and advantages of this invention will become apparent fromthe description following when read in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a view in elevation and partially in section of a carburetorwith a protective cover embodying features of this invention shown inplace;

FIG. 2 is a view in elevation viewed from one side of the protectivecover;

FIG. 3 is a top view of the protective cover; and

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FIG. 4 is a section view taken along line 44 of FIG. 3.

Referring to the drawings in greater detail, the protective cover 10 isparticularly adapted for use in a motorcycle carburetor 12 including anair intake 14, a main body portion 16 and an outlet passage 18.

Certain other features such as a throttle adjusting screw 20 and themain and pilot jet covers 22 and 24 are shown in FIG. 1 but they have nobearing on the present invention and will not be described in detail.

The upper end of the cylindrical main body portion 16 is threaded at 26to accommodate a complementary threaded coupling member 28 having aninternal flange 30 at the upper end thereof which engages an externalflange 32 at the lower end of the carburetor cap 34. One or moreconduits 36 open into the carburetor cap to conduct suitable memberssuch as a throttle adjustment cable 38 into the main mixing chamber.Preferably, a spring clip 40 extends out and down from the top of thecap to engage the coupling member under slight pressure to preventinadvertent loosening thereof.

Carburetors of the type just described are in wide use in small internalcombustion engines, particularly those installed in motorcycles. Suchcarburetors have proved extremely effective, but the major difficultyexperienced has been in the tendency for vacuum within the carburetorbody to draw ambient air in through the minute clearance between thecoupling flange 30 and the cap flange 32 and into the interior of thebody 16. A further entry clearance for ambient air may exist atrecoupling 37 of the cable conduit 36 connected into the carburetormixing chamber cap 34. Such entry clearances often permit entry of notonly ambient air, but any dirt, moisture or the like carried thereby.

In association with the above-described carburetor, my protective cover10 comprises a cup-like member of rubber, plastic or like material thatis stretchable. The main body portion of the cover is generallycylindrical in horizontal cross section and is of an internal diameterlarger than that of the threaded coupling 26 for the carburetor cap 34,as clearly seen in FIG. 1, The central cover portion is of suflicientaxial length to extend from above the top of the carburetor cap to apoint on the main body portion 16 of the carburetor below the threadedcoupling 26 so that the threaded connection is completely covered butpreferably not fricti'onally engaged by the protective cover.

Below the cylindrical central cover portion 42 the protective coverreduces in diameter to a relatively narrow band 44, at the lower end ofwhich is a beaded rim 46. The narrow band is of a diameter slightly lessthan the diameter of the cylindrical main body portion of the carburetorso that it must be stretched over the carburetor body to embrace ittightly under some tension when in place in order to effect a seal.

Integral with and extending upwardly from the top of the cup-likeprotective cover is a tubular extension 48 which is also surrounded atits open upper end by a beaded rim 50. The beaded rim is of an internaldiameter slightly less than that of the conduit 36 over which it engagesso that again, the conduit is engaged tightly with the bead under slighttension to form a tight seal against entry of foreign matter. While onlyone tubular protuberance 48 is shown, it is to be understood that thenumber thereof is dependent upon the number of conduits 36 to be sealedoff. Thus, in certain carburetors 12 of the type described the air valve(not shown) is also cable controlled and provision should be made toseal around it as well.

In order to accommodate the threaded coupling retainer clip 40, Iprovide a lateral extension 52 which is formed integral with the centralcover portion 42 to ex- 3 tend upward at 54 from the top surface 56 andlaterally at 58 from one side in a generally rectangular horizontalcross section as shown in FIG. 3 to provide ample room for accommodationof the spring clip without subjecting it to compressive forces thatmight tend to disturb the setting.

It is apparent that with the protective cover 10 described, it may beplaced over a carburetor 12 after directing the cable adjustment conduit36 through the upstanding tubular extension 48. The cover is stretchedslightly to pull it over the spring clip 40 and coupling member 26 thenreleased so that it engages the main body portion 16 snugly while underslight tension. With the protective cover 10 so placed, the carburetorWiring chamber cap 34, the coupling 26 and the cable connection 37 arecompletely enclosed and sealed from the ambient air. As such, the cover10 constitutes a sealed vessel encasing the carburetor cap against entryof moisture, dirt and other foreign particles.

While this invention has been described in connection with a preferredembodiment thereof, it is apparent that modifications and changestherein may be made by those skilled in the art without departing fromthe spirit and scope of this invention as defined by the claims appendedhereto.

Having described my invention, I claim:

1. A carburetor having a body portion, a top cap portion threadedlyattached on said body portion, at least one conduit opening into saidcap portion, and a protective covering comprising:

a cup-like member of resilient material having a closed upper end and adepending. kirt portion terminating in an open bottom,

the peripheral length of said open bottom being normally no larger thanthe girth of the body portion of said carburetor,

the length of said skirt portion being greater than the distance fromthe top of the cap portion of said carburetor to its threaded connectionwith said body portion, and

at least one'tubular extension being positioned on said upper end inaccordance with the position of said conduit on the cap portion of saidcarburetor,

the circumference of said tubular extension being normally no largerthan the circumference of said conduit.

2. The carburetor defined by claim 1 including:

a first beaded lip around and integral with said open bottom, and

a second beaded lip around and integral with the open upper end of saidtubular extension.

3. The carburetor defined by claim 2 wherein:

said first and second beaded lips are normally of a peripheral lengthless than the girths of said carburetor body portion and said conduit,respectively.

4. The carbuertor defined by claim 1 wherein:

the cross section of said skirt portion is enlarged above said openbottom to a cross section larger than the cross section of the threadedconnection between the cap portion and body portion of said carburetor.

5. The carburetor defined by claim 1 having a spring clip depending fromone side of said cap portion to engage the threaded connection betweensaid cap portion and said body portion, said cover including:

an integral hollow extension extending laterally from said upper end andskirt portion and opening into the internal surfaces thereof toaccommodate said spring clip. 6. A carburetor having a cylindrical bodyportion, a top cap portion threadedly attached on said body portion, aconduit opening into said cap portion, and a protective coveringcomprising:

an open bottom, generally cylindrical cup-like member of resilientmaterial having a closed upper end and a depending skirt portionterminating in an annular band of reduced diameter around the openbottom,

the diameter of said annular band being normally no larger than thediameter of the body portion of said carburetor,

the length of said skirt portion to said annular band being greater thanthe distance from the top of the cap portion of said carburetor to itsthreaded connection with said body portion, and

a tubular extension integral with said closed upper end and extendingupwardly therefrom,

said tubular extension being positioned on said upper end in accordancewith the position of the conduit on the cap portion of said carburetor,

the circumference of said tubular extension being normally no largerthan the circumference of said conduit.

7. The carburetor defined by claim 6 including:

a first beaded lip around and integral with said open bottom, and

a second beaded lip around and integral with the open upper end of saidtubular extension,

said first and second beaded lips being normally of diameters less thanthe diameters of said carburetor body portion and conduit, respectively.

8. The carburetor defined by claim 6 having a spring clip depending fromone side of said cap portion to engage the threaded connection betweensaid cap portion and said body portion, said cover including:

an integral hollow extension of generally rectangular horizontal crosssection extending laterally from said upper end and skirt portion andopening into the internal surfaces thereof to accommodate said springclip.

References Cited by the Examiner UNITED STATES PATENTS 2,756,033 7/1956Smith et al. 261-44 2,786,658 3/1957 Duriez 26144 X FOREIGN PATENTS742,352 12/1932 France. 732,377 3/1943 Germany.

OTHER REFERENCES Ser. No. 369,721, Fiedler (A.P.C.), published June 15,1943.

HARRY B. THORNTON, Primal Examiner.

RONALD R. WEAVER, Examiner.

1. A CARBURETOR HAVING A BODY PORTION, A TOP CAP PORTION THREADEDLYATTACHED ON SAID BODY PORTION, AT LEAST ONE CONDUIT OPENING INTO SAIDCAP PORTION, AND A PROTECTIVE COVERING COMPRISING: A CUP-LIKE MEMBER OFRESILIENT MATERIAL HAVING A CLOSED UPPER END AND A DEPENDING SKIRTPORTION TERMINATING IN AN OPEN BOTTOM, THE PERIPHERAL LENGTH OF SAIDOPEN BOTTOM BEING NORMALLY NO LARGER THAN THE GIRTH OF THE BODY PORTIONOF SAID CARBURETOR, THE LENGTH OF SAID SKIRT PORTION BEING GREATER THANTHE DISTANCE FROM THE TOP OF THE CAP PORTION OF SAID CARBURETOR TO ITSTHREADED CONNECTION WITH SAID BODY PORTION, AND AT LEAST ONE TUBULAREXTENSION BEING POSITIONED ON SAID UPPER END IN ACCORDANCE WITH THEPOSITION OF SAID CONDUIT ON THE CAP PORTION OF SAID CARBURETOR, THECIRCUMFERENCE OF SAID TUBULAR EXTENSION BEING NORMALLY NO LARGER THANTHE CIRCUMFERENCE OF SAID CONDUIT.